Welding torches are often used in conjunction with a robotic unit. This is particularly advantageous in a manufacturing setting where multiple welds are needed in a precise fashion. Two types of welding torches often used with robotic units are metal inert gas (“MIG”) welding torches and tungsten inert gas (“TIG”) welding torches. When used with a robotic unit, the welding torch may be fastened to the robotic unit, at a robotic interface and supplied with electrical current, electrode wire, a supply of inert gas, and a supply of coolant. Such materials are typically provided to the welding torch via one or more cable assemblies.
Metal inert gas (“MIG”) welding torches may be used in a variety of applications. MIG welding torches are used primarily in industrial welding applications due to the need to protect the welding area from atmospheric oxygen and/or nitrogen. During the MIG welding process, an electrode wire is supplied to the tip of the welding apparatus. An electrical arc is then provided which acts to heat and melt the electrode wire causing the electrode wire to be applied on the workpiece. Based on the reactivity of the molten electrode wire with oxygen and/or nitrogen in the atmosphere, a stream of inert gas, such as helium or argon, is directed over the molten electrode wire to prevent oxygen and/or nitrogen from contacting the molten electrode wire and adversely affecting the integrity of the weld.
Tungsten inert gas (“TIG”) welding torches may be used in a variety of applications. TIG welding torches are used primarily in welding applications involving thin work pieces such as piping. TIG welding is also used in the aerospace industry due to the ability to weld thin workpieces and the ability to weld materials such as aluminum TIG welding utilizes a non-consumable tungsten electrode. Tungsten is selected as the electrode material of choice based on it high melting point. During the TIG welding process, an electrical arc is struck between the tungsten electrode and the work piece. The electrical arc may cause the work piece to melt thereby creating a weld pool. A filler wire may be supplied to an area proximate to the tungsten electrode whereby the electrical arc acts to heat and melt the filler wire causing the melted filler wire to be applied on the workpiece. Based on the reactivity of the molten filler wire or the molten workpiece with oxygen and/or nitrogen in the atmosphere, a stream of inert gas, such as helium or argon, is directed over the weld pool to prevent oxygen and/or nitrogen from contaminating the weld pool and adversely affecting the integrity of the weld.
Current designs of such robotic torches in the industry are installed in a fixed position throughout an arm/or thru arm, to the robotic interface and during the welding process the robot must twist the cables in order to turn the robotic torch around. This becomes a problem, as the cables (whether fixed or rotary), are subjected to severe mechanical wear during articulation of the robotic arm. This mechanical wear can result in coolant leak and voltage variation which may adversely affect the welding process and the quality of the final weld. As such there is a need in the art for a robotic welding torch which provides for rotation without damaging one or more of the supply cables connected to the robotic welding torch.